Table 1.

Positive Predictive Values (PPVs) for Incident and Recurrent Stroke

	Confirmed Cases (Yes/No)	PPV (95% CI)
Incident Stroke
All codes	Yes=70, No=5	0.93 (0.88, 0.99)
I63.0x	Yes=1, No=0	1.0 (1.0, 1.0)
I63.1x	Yes=3, No=1	0.75 (0.33, 1.0)
I63.2x	Yes=4, No=0	1.0 (1.0, 1.0)
I63.3x	Yes=2, No=0	1.0 (1.0, 1.0)
I63.4x	Yes=12, No=0	1.0 (1.0, 1.0)
I63.5x	Yes=12, No=0	1.0 (1.0, 1.0)
I63.8x	Yes=2, No=0	1.0 (1.0, 1.0)
I63.9	Yes=34, No=4	0.89 (0.80, 0.99)
Recurrent Stroke
All codes	Yes=54, No=21	0.72 (0.62, 0.82)
I63.0x	Yes=3, No=1	0.75 (0.33, 1.0)
I63.1x	Yes=2, No=0	1.0 (1.0, 1.0)
I63.2x	Yes=4, No=8	0.33 (0.07, 0.60)
I63.3x	Yes=0, No=0	N/A
I63.4x	Yes=17, No=0	1.0 (1.0, 1.0)
I63.5x	Yes=9, No=1	0.90 (0.71, 1.0)
I63.8x	Yes=1, No=0	1.0 (1.0, 1.0)
I63.9	Yes=18, No=11	0.62 (0.44, 0.80)
Recurrent Stroke Stratified by Gaps between the First and Second Stroke
≤20 Days	Yes=15, No=8	0.65 (0.46, 0.85)
>20 Days	Yes=39, No=13	0.75 (0.63, 0.87)
≤30 Days	Yes=21, No=9	0.70 (0.54, 0.86)
>30 Days	Yes=33, No=12	0.73 (0.60, 0.86)
≤45 Days	Yes=26, No=11	0.70 (0.56, 0.85)
>45 Days	Yes=28, No=10	0.74 (0.60, 0.88)
≤60 Days	Yes=30, No=13	0.70 (0.56, 0.83)
>60 Days	Yes=24, No=8	0.75 (0.60, 0.90)
≤90 Days	Yes=36, No=13	0.73 (0.61, 0.86)
>90 Days	Yes=18, No=8	0.69 (0.51, 0.87)
≤180 Days	Yes=40, No=14	0.74 (0.62, 0.86)
>180 Days	Yes=14, No=7	0.67 (0.47, 0.87)
≤365 Days	Yes=44, No=17	0.72 (0.61, 0.83)
>365 Days	Yes=10, No=4	0.71 (0.48, 0.95)
Recurrent Stroke after Removing Hospital Admissions related to Stroke-Related Procedures *	Yes=50, No=14	0.78 (0.68, 0.88)

All reviewed cases included ICD codes I63.x. There was no recurrent stroke case identified by G46.3 or G46.42 codes. *Carotid endarterectomy, transcarotid artery revascularization, or carotid artery stenting procedures (CPT codes: 35301, 37215, 37217)